In Depth Stratesaurus represents a genus of rhomaleosaurid plesiosaur, a type of plesiosaur noted for having a shorter neck and proportionately larger head than other plesiosaurs, though not to the extent of pliosaurs. The discovery of Stratesaurus in Hettangian aged rocks means that individual Stratesaurus were swimming in European waters near the Triassic/Jurassic boundary, which … Read more
In Depth While the plesiosaurs are usually seen as predators of fish Aristonectes took the different and much more specialist path of filter feeder. The teeth in the jaws were very short with crowns that were less than one centimetre high. There were a high number of these teeth which were densely packed together in … Read more
In Depth Palmulasaurus was initially named as Palmula when first described in 2007, but it was soon realised that Palmula was actually preoccupied by a genus of foraminifer (an amoeboid protist), hence the later addition of the Ancient Greek ‘saurus’ which means ‘lizard’. In 2007 Albright, Gillette and Titus also named of polycotylid plesiosaur from … Read more
In Depth Anningasaura was named in honour of Mary Anning. Mary Anning lived in the early nineteenth century, and spent a lifetime collecting fossils on the shorelines of Dorset, many of which were sold in her families shop in Lyme Regis. Anning’s discoveries and contributions to science would eventually lead to worldwide recognition of her … Read more
In Depth Discovered in New Zealand, Mauisaurus was for a long time credited as one of the largest plesiosaurs. However in more recent times there have been doubts about the validity of fossils attributed to the genus since these have come from so many different locations. Mauisaurus also displays the long sharp teeth often seen … Read more
In Depth Thalassomedon is regarded as a mid-sized elasmosaurid plesiosaur, especially when compared with larger genera like Mauisaurus. The distribution of Thalassomedon remains show that it swam in the Western Interior Seaway, a Cretaceous sea that divided North America into two halves. Thalassomedon is so far only known from the early stages of the Late … Read more
In Depth Although many of the placodonts had shells only a few like Henodus and Placochelys had single shells that covered the entire body, while others like Cyamodus had two shells. Henodus has one of the most well developed single shells of all placodonts made up by a fusion of a large number of scutes … Read more
In Depth Fresnosaurus was a late Cretaceous era elasmosaurid plesiosaur that seems to have the signature feature of this group of a very long neck proportionately greater than in earlier and more primitive plesiosaur forms. Like with these other genera, Fresnosaurus was probably a specialist hunter of fish and soft bodied cephalopods like squid. Fresnosaurus … Read more
In Depth Another plesiosaur named Kimmerosaurus is known from the Kimmeridge Clay, and interestingly while Colymbosaurus is known only from incomplete post cranial remains, Kimmerosaurus is known only from the skull and a few cervical vertebra. This has led to speculation that the two genera are actually one and the same species. However, only the … Read more
In Depth Albertonectes is one of the best preserved elasmosaurid plesiosaurs to be discovered in Canada, and has a total of 76 cervical (neck) vertebrae . Elasmosaurid pesiosaurs like Albertonectes are noted for having their long necks that are proportionately much longer than earlier plesiosaur types. This would have been a specialist feeding adaptation allowing … Read more